With some 2.7 million communications from the US State Department about to be published online, Mr Obama is bracing himself for revelations that would not only be embarrassing but could also seriously damage his foreign policy.

Thousands of these documents are believed to be diplomatic cables from Washington to the US Embassy in London, including brutal assessments of Gordon Brown's personality and cold-eyed judgements of David Cameron's capabilities.

The ramifications for Mr Obama could be enormous. With his popularity flagging at home, one of his remaining political strengths has been his high standing abroad - assiduously cultivated in a series of speeches in which he apologised for past US actions and promised a kinder, gentler America.

This could really ruin Barack's reputation. Assange and all the other mean girls at WikLeaks can be soooo cruel.

(But as bad as it will be for American foreign policy to have these diplomatic messages on display to the world, it will be fascinating to see whether Obama is as obsequious in private to all the world leaders he's bowed to in public.)